You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither SPIE nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the SPIE website.
8 March 2014Traveling wave electrode design for ultra compact carrier-injection HBT-based electroabsorption modulator in a 130nm BiCMOS process
Silicon photonic system, integrating photonic and electronic signal processing circuits in low-cost silicon CMOS
processes, is a rapidly evolving area of research. The silicon electroabsorption modulator (EAM) is a key photonic
device for emerging high capacity telecommunication networks to meet ever growing computing demands. To replace
traditional large footprint Mach-Zehnder Interferometer (MZI) type modulators several small footprint modulators are
being researched. Carrier-injection modulators can provide large free carrier density change, high modulation efficiency,
and compact footprint. The large optical bandwidth and ultra-fast transit times of 130nm HBT devices make the carrierinjection
HBT-based EAM (HBT-EAM) a good candidate for ultra-high-speed optical networks.
This paper presents the design and 3D full-wave simulation results of a traveling wave electrode (TWE) structure to
increase the modulation speed of a carrier-injection HBT-EAM device. A monolithic TWE design for an 180um ultra
compact carrier-injection-based HBT-EAM implemented in a commercial 130nm SiGe BiCMOS process is discussed.
The modulator is electrically modeled at the desired bias voltage and included in a 3D full-wave simulation using CST
software. The simulation shows the TWE has a S11 lower than -15.31dB and a S21 better than -0.96dB covering a
bandwidth from DC-60GHz. The electrical wave phase velocity is designed close to the optical wave phase velocity for
optimal modulation speed. The 3D TWE design conforms to the design rules of the BiCMOS process. Simulation results
show an overall increase in modulator data rate from 10Gbps to 60Gbps using the TWE structure.